GitHub Actions setup-go "Unable to find Go version"

By Kaveh Alemi·Latchkey

actions/setup-go resolves go-version (or go-version-file) against the official Go release feed. A non-existent version, or a go.mod that pins a toolchain with no published build, fails resolution.

What this error means

A setup-go step fails resolving the version, often after a typo, a yanked patch, or a go.mod toolchain line pointing at an unreleased version.

Error: Unable to find Go version '1.23.99' for platform linux and architecture amd64.

Common causes

Version not in the Go release feed

setup-go matches against published Go releases; a version that was never released for the platform cannot be found.

go-version-file points at an unpublished toolchain

A go.mod toolchain directive or .go-version file requesting an unreleased version drives the same failure.

How to fix it

Pin a published version or use a range

1. Use a minor spec like 1.23.x so setup-go selects the newest published patch.
2. If using go-version-file, confirm the toolchain in go.mod is released.
3. Avoid hand-typed exact patches that may not exist.

- uses: actions/setup-go@v5
  with:
    go-version: '1.23.x'

How to prevent it

• Prefer a minor range (1.23.x) over an exact patch in CI.
• Keep go.mod toolchain and the workflow go-version aligned.
• Latchkey managed runners auto-retry the Go download on transient network failures and keep recent toolchains in a warm cache.

Frequently asked questions

Related guides

References

• GitHub Actions documentation
• Workflow syntax for GitHub Actions